Since plastic lenses are light, not easily cracked, and can be stained in comparison to inorganic lenses, plastic lenses have been rapidly distributed as optical elements such as spectacle lenses and camera lenses, and hitherto, a variety of resins for spectacle lenses have been developed and used. Among these, representative examples include an allyl resin obtained from diethylene glycol bisallyl carbonate and diallyl isophthalate, a (meth)acrylic resin obtained from (meth)acrylate, and a polythiourethane resin obtained from isocyanate and thiol.
In recent years, plastic photochromic lenses using organic photochromic dyes are commercially available as glasses. Examples of techniques in the related art for the photochromic lenses include the following.
Patent Document 1 describes that by combining a specific aromatic (meth)acrylic acid ester and an aromatic vinyl, favorable light adjusting performance is obtained.
Patent Document 2 describes a lens formed of a composition including a predetermined photochromic compound and a di(meth)acrylate compound. In paragraph [0009], it is described that in a case where a urethane resin or a thiourethane resin having a high refractive index is used, isocyanate which is a resin raw material in a monomer state reacts with the photochromic compound, and due to this, photochromic performance is completely eliminated.
Patent Document 3 discloses a lens obtained by providing a coating layer formed of a composition including a photochromic compound having a chromene skeleton and a phenol compound on a surface of a thiourethane-based plastic lens.
Patent Document 4 discloses a photochromic lens having a lens substrate formed of a thiourethane resin and a photochromic film formed by applying a solution including a photochromic compound and a radically polymerizable monomer on the substrate.
Patent Document 5 discloses a compound having photochromic characteristics.
Patent Document 6 describes a process for producing a photochromic optical material by curing a monomer composition including a photochromic compound, a polythiol, and a polyether.
Patent Document 7 discloses an optical resin composition containing a thiol-ene prepolymer.